1. Field of the Invention
This invention relates generally to battery monitoring systems and, more particularly, to real-time battery State of Health detection utilizing a Matrix of battery Parameters.
2. Description of the Related Art
State of health recognition for a rechargeable battery is an important element of the total battery management in order to ensure proper operation of electrical systems operated by the battery. State of health can be considered as current state of charge, useful remaining life as a function of life cycle, and useful remaining discharge time as a function of the current discharge rate.
Prior art techniques for discovering battery state of health generally only analyze current and voltage behavior by examining a battery utilizing an electronics approach. That is, prior art approaches examine the battery as though the battery were a transistor, and use a transistor analysis to categorize the battery. By way of example, U.S. Pat. No. 6,956,355 describes a self-diagnosis system for an energy storage device, the latter including a plurality of electrochemical cells connected in series or parallel to form a cell string. The self-diagnosis system correlates a state of health of the battery based on the internal resistance value of each electrochemical cell of the energy storage device and determines a corresponding battery initial capacity which enables the self-diagnosis system to evaluate the exact capacity of the battery at any given time.
Unfortunately, batteries operate under much more complicated physical conditions than electronic devices. For example, physical conditions for batteries include simultaneously charge, mass and heat unstationary transfer in three phase environments, which are much more complicated than the operating condition of single solid state electronic devices. In view of the foregoing, there is a need for systems and methods for real-time battery State of Health detection. In particular, the systems and methods should examine intrinsic battery parameters to determine the battery's state of health.